It is difficult to get a handle on Mr. Peabody & Sherman, because on the one hand it is a cartoon intended to be absurd and unrealistic in some ways, and on the other it deals with reality in ways to which we can relate.  When Penny Peterson picks a fight with Sherman and is choking him, and Sherman gets in trouble not only with the school but with the Bureau of Child Safety and Protection for biting her to escape, we recognize the problems and inequities in school violence situations.  When a round manhole cover in Paris is knocked into the air and then returns to fall through its manhole and hit someone below, we are hit by problems ranging from simple geometry (round manhole covers cannot fall through their own holes no matter how they are turned) to cartoon violence (in reality, such a blow would almost certainly have been fatal).  Thus we are confronted by absurdities mixed with serious realities in a way that is quite entertaining but not easy to analyze.

But we will try.

The characters and their situation are drawn from the Jay Ward cartoon series Peabody's Improbable History, companions of Rocky and His Friends, Fractured Fairy Tales, and Dudley Do-Right.  The simple story of an intelligent dog, Mr. Peabody, adopting a boy, Sherman, as his own son is expanded so that Peabody is something of an action adventure hero in addition to an inventive genius.  Before his first day of school, Sherman has already traveled through history with his adoptive father, meeting George Washington and seeing several moments in history.  We participate in his visit to the French Revolution, and the slapstick escape from the Reign of Terror.

Then on his first day of school Sherman becomes the know-it-all and so incurs the wrath of bully Penny Peterson, leading to the aforementioned fight.  Miss Grunion of the aforementioned Child Safety agency already has her prejudice, that no dog, not even an Olympic medalist, Harvard alumnus, and successful business titan, should ever have been permitted to adopt a human boy, and intends to use this incident to terminate that relationship.  Mr. Peabody theorizes that he might be able to fix the problem by inviting the Petersons over for dinner, getting the kids to work through their disagreements, and so getting the complaint rescinded.  However, while Sherman is trying to defend his first-hand knowledge of George Washington, he reveals the existence of the secret WABAC machine, and she insists that they use it.  The next thing we know, Sherman is trying to explain to Mr. Peabody how he managed to lose Penny in ancient Egypt, and the intrepid duo attempts to leave her parents at their party while they rush to the past to rescue the girl.  Things do not go smoothly, with the result that they bounce through several places in time and space, lose Mr. Peabody, get his younger self to assist in rescuing his older self, and stumble into a major temporal crisis which only they can resolve.

All of this presents problems, most of them already familiar to us from other films but some of them a bit creative.  We will begin at the beginning next time.

The first problem we face is that we are given the impression of numerous previous trips to the past about which we know almost nothing.  The Tower of Pisa was not always leaning; Sherman asked George Washington about the cherry tree story; Leonardo DaVinci is a good friend of Mr. Peabody.  We know that these events sometimes changed history in some ways, but we do not even know all the trips let alone all the problems.

One that is clearly a change that has serious ramifications involves the Tower of Pisa.  Sherman suggests that something they did caused it to lean.  (Obviously in one sense the tower was not always leaning--it was originally built plumb, but uneven settling of the foundation causes it to tilt a bit more each year.)  The hidden question is why they were there at all.  The Tower has two aspects which create interest in it.  The obvious one is that it is tilted--not built that way, but it is still fascinating to see a tower several stories tall whose top is not directly over its base.  If the tower is not leaning, it is not different from many others and not particularly interesting for tourists including Sherman.  The other aspect is that it is a famous location because of Galileo's famous gravity experiment, in which he proved that a heavier (more massive) object does not fall faster than a lighter (less massive) one by dropping two such objects from the tower simultaneously and demonstrating that they hit the ground simultaneously.  (This disproved Aristotle's accepted "logical" physics law that heavier objects fall faster than light ones.)  So if the tower is not leaning it still might be famous because of this experiment.  However, that is problematic.  The obvious advantage of the tower to Galileo's experiment is precisely that the top is not over the base--that is, if one goes up to the upper levels and looks over the rail, on one side there is a straight drop to the ground.  Towers and steeples, and indeed most skyscrapers today, are narrower at the top than at the bottom, and thus objects dropped from the top will hit the external walls on the way to the ground.  Throwing the object away from the building would prevent this, but also invalidate the drop experiment.  Galileo could perform the experiment precisely because the tower allowed him to drop two objects and have them fall directly to the ground.  If the tower were not leaning, it would not be famous for either reason, and there would have been no reason for Peabody to take Sherman there.  Further, the tower would not be famous in our time, and Galileo would have had to have found some other way to perform his experiment--perhaps building a tall scaffolding with an extended balcony, or finding a cliff, or building an abutment on some other building for the purpose.

Obviously Peabody took Sherman to Pisa to see the famous tower; but if so, the tower was already leaning, and Sherman knows nothing of it not leaning.

We mentioned that it is difficult to distinguish when it is being cartoonishly absurd.  This proves to be one of those absurdities--a throwaway joke line that is barely funny and suggests what proves to be nearly impossible.  We might suppose that Peabody visited Pisa for some other reason, that the duo accidentally disturbed the foundation of the tower, and that it thereafter gained a place in history--but that creates a separate problem, the problem that the Sherman born and raised in the future in which the tower was always leaning would not have known it was ever not leaning.  We would have to suppose that sometime before Galileo's experiment the duo had their accident which tilted the tower, that in the repeat of history that accident was preserved, and that Sherman means only that they were the cause of the lean in that tower which in the history he knows has been leaning since their visit.  It would then seem that they did not change history, but only made it what it always was--which is how N-jumps appear in replacement theory, and how history always works under fixed time theory.

The apparently careless time travelers have caused other problems, and before we examine the trips we see in detail we will touch on those for which we get mere glimpses.

There have been several trips to the past suggested within the film prior to its opening, and we addressed one.  Most of the others appear in a montage of memories and photographs in which Sherman ice skates in the ice age, catches a Jackie Robinson homer, flies a kite with Franklin, swims with Baby Moses, and flies with the Wright Brothers.  All of these are plausible, minor changes to history which might have serious ramifications (why are they not mentioned in historic accounts, and did they deprive someone else of a place in history--such as who caught that baseball before Sherman stole it).  There are two, however, which might be very serious.  In one, Mr. Peabody hands his finished and signed manuscript of a play to William Shakespeare, who clearly is to publish it as his own.  In the other, Sherman paints some swirling images which immediately inspire van Gogh to paint The Starry Night.  The problem is that this nearly demands that those famous works did not exist in the original history but came into existence in the altered history due to the tinkering of our time travelers.

In the case of The Starry Night, it is significant but possibly not critical.  While that is the most recognized of van Gogh's paintings, it is far from the only famous one, and he probably would have been famous (and perhaps a different painting his most recognized work) without it.  It is possible that in creating this painting he did not create some other one--oil paintings are not usually finished in a few hours despite PBS instructional videos showing how to do this, so the time he spent painting one painting is time he did not spend painting another.  However, it is difficult to imagine that this hypothetical other painting in the erased original history would have been more famous than the one we know, and so the impact on van Gogh is probably not major.  There are separate questions related to the impact of the painting on others, such as Don McLean, so history is altered, but most of it is probably in the artistic realm of recent decades and has no direct impact on the time travelers.

The Shakespeare problem is more serious, however.  Certainly the Bard was prolific enough that we might accept the possibility that someone ghosted one of his plays for him (it is a recurring argument among Shakespearean scholars as to whether William wrote all or even any of them).  The problem is that in signing Shakespeare's name to the manuscript Peabody suggests to us that he wrote all of Shakespeare's plays (because it suggests that his handwriting would be recognized as genuine Shakespeare).  It certainly is one thing to argue that all of the plays attributed to the Stratford-on-Avon actor were ghosted by Francis Bacon or Christopher Marlowe; that is a question for literary critics.  However, if they were written by a time traveler from the future, suddenly we have a serious connundrum.  Assuming that Shakespeare never wrote a play (and none of his contemporaries provided him with these), why would anyone remember him?  It only makes sense for our future time traveler to ghost for Shakespeare if Shakespeare is already a famous playwright in the future--and in that case, the ghost writer cannot sign Shakespeare's signature to the manuscript but must give it to the Bard unsigned.  A traveler from the future writing all the Shakespearean plays and giving them to Shakespeare in the past would ultimately have picked someone almost at random to be his front.

Further, any play or plays written by our future ghost writer would not have existed in the original history.  It might be argued that there are a few plays not so well known that could have been omitted without impacting the fame of the playwright, and we can reasonably assume that this is not Hamlet or MacBeth or Romeo and Juliet (Shakespeare laughs when he reads it, so it is probably one of the comedies).  Yet given the influence these works have had on all of world literature and more recently film, the notion of adding a play to the ouvre is at best hazardous.  Its impact on history would be potentially significant, and the more so if it were a great one.

To resolve that, we will have to assume that the signature part is a flourish that should have been excluded.  Peabody might have provided one play for Shakespeare, but he did not sign it.

There is also the aspect that many people in history are apparently aware of Peabody and Sherman traveling from the future to visit the past, and thus that time travel will be possible; none of them seem to have reported this, although perhaps because even less credible than that someone traveled through time is that the time travelers were a dog and his boy.

On that note, we can move to the first trip we actually see.

The first trip to the past we actually see in the movie is the one made to 1789 to the decadent opulent Palace of Versailles mere hours before the French Revolution.  We see Marie Antoinette, portrayed as terribly overindulgent in her love for what we call cake, make her famous statement demonstrating her complete lack of understanding of the plight of the peasants (that having no bread would not be a problem because they can substitute cake for it).  Within minutes word of this callousness spreads throughout Paris, the peasants revolt, and the palace is overrun, everyone within imprisoned and sentenced to execution including Mr. Peabody (but not, it seems, Sherman).  He was caught because Sherman had wandered into the kitchens in search of more cakes, and so he could not effect their getaway in time.

Improbably, Peabody escapes from the guillotine and leads Robespiere and his soldiers on a merry chase through the Parisian sewers.  By igniting the collected methane to create an explosion, Peabody engineers a brilliant egress.

Of course, strictly logically there must have been hundreds, perhaps thousands, of deaths from such an explosion under the city; there certainly is no way that Robespiere could have survived unscathed.  This, though, is a cartoon explosion, propelling the heroes several miles through the air to a skillfully smooth landing outside the city while leaving their pursuers with nothing worse than sooty faces and tattered clothes.  We again have one of those absurd events, this time which can only happen in cartoons.  It seems that the duo have changed history without killing anyone, and so have not directly impacted their own future.  The daring escape of one unidentified noble dog is unlikely to be more than a footnote in the history books, particularly as Robespiere will undoubtedly have it reported that he was killed trying to escape.

We would also expect an explosion of that magnitude to have devastating effects on buildings and sewers and substructures in Paris, but again it is a cartoon explosion and apparently has no harmful effects at all.  It is one of those movie events that could not happen in reality not because of the laws of time travel but because of those laws of physics which are routinely ignored in cartoons.  If you grasp the concepts so ably presented in Who Framed Roger Rabbit concerning the nature of Toons and their world, you understand that none of these people or places are subject to the same laws of physics as our reality.

That does not, however, mean that they are not subject to the same logical rules of time.

Sherman mentions to Penny that he met George Washington, and has to prove it by showing her the WABAC machine, which she insists on using.  (Yes, the lovely Penny Peterson is a spoiled brat and a nag in addition to being a bully.)  We are given that Sherman takes her to meet George Washington.  It is unclear what other stops they may have made, but ultimately they visit ancient Egypt, where Penny is separated from Sherman, who decides he cannot rescue her and must get help from Mr. Peabody, so he returns to the party where the dog is entertaining the Peterson parents and enlists his aid.  This introduces the main trip of the story, but it gives us a preliminary trip of some concern.

Since we are unclear as to when else the young couple visited we will simplify the trip to those two stops in that sequence.  We date Washington to the late eighteenth/early nineteenth century; we are given 1332 B.C. as the date for the Egypt stop.  That means we have two anomalies to resolve, the first because Sherman traveled from the present to the eighteenth century, the second because he traveled from a very short time later in the eighteenth century to a more distant past.

To clarify, Sherman and Penny are born in the twenty-first century, a time that came into existence without their appearance in the past.  They then departed from that century after a few years and traveled to the late eighteenth (or early nineteenth) century.  This changes history to the degree that they are now present in events in which they were not previously involved.  At the very least, it changes what George Washington did that day.  It is at least remotely possible that something they did would cause one of them, or the time machine, never to have existed, or to change events such that they never made the trip.  However, before we resolve this the new history is changed again, they leave from the nineteenth century and head back 1332 B.C.  This introduces a second anomaly arising from the first.

Somehow Penny is separated from Sherman, who escapes and returns to his own time.  This is significant.  In order for Sherman to reach the present, he must leap across thirty-three centuries all of which must be re-written to account for changes made by his visit to the past.  However, before he reaches the twenty-first century he passes the early nineteenth, and thus all of history from Tutenkamen to Washington has to resolve in a way that brings Sherman and Penny to see Washington and then to leave bound for Egypt.  It seems unlikely that anything that happened as long ago as ancient Egypt would impact events in the thirteen United States, but through all of this Penny Peterson is stuck in that past.  She became the bride of Pharaoh Tutenkamen (a.k.a. King Tut) and died in the past.  No one can come to rescue her from the future, because the future has to be rewritten before they can depart from it.  Since we know Tut died young, she was entombed with him, executed and embalmed, and there will be a mummy of her at whatever age she was when he died.  She will have enjoyed a brief reign as consort to the king of perhaps the most powerful nation in the world at that time, but probably will not in retrospect think it worth the price.  Our concern, ultimately, is the genetic problem:  whether Tut and Penny had a child they obviously would not otherwise have had, whether by marrying Penny Tut failed to marry someone else, someone he would or might have married instead married someone else and had a child, in short, whether Penny's interference with the marriages in Tut's court resulted in a change in the identities of any Egyptians in the next generation.  Such a change would have a ripple effect, and given that it is so close to the line of rulers in Egypt it might mean that some other Pharaoh made different decisions that had different effects on world politics--Cleopatra might never have been born, for example.

Even if somehow Penny's presence has no genetic impact, it still seems likely that there would be some mention of Tut's exotic light-skinned blonde-haired blue-eyed bride--highly unusual characteristics in that part of the world at that time.  Our archaeology and ancient history would be impacted to some small degree, and there would be doctoral theses on the origin of this strange woman.  That incidentally means that other doctoral theses, the ones these learned men would have written, will never have been produced.  The impact on the world of knowledge is difficult to assess.

Once the anomaly created by the trip to Egypt resolves as far as Washington, Sherman continues to the present, and the history created by his changes to the life of our first President must stabilize to the point that he and Penny are the same people making the same trip, in order for them to confirm their presence in the past.  They cannot be there if that does not happen, and it would result in an infinity loop.  We again expect that this will resolve to an N-jump, that it is certainly possible that nothing Sherman and Penny did will prevent them from being the same people making the same trip to do what they did, and so Sherman can arrive in the future and contact Mr. Peabody.  The good news is that history is stable; the bad news is that the Petersons and Miss Grunion are going to be very upset about the absence of the presumptively innocent little girl (it is definitely discriminatory that boys are always presumed guilty in conflicts with girls) if they do not return her promptly.  That introduces the next trip.

Mr. Peabody takes Sherman back to 1332 B.C. Egypt where they rescue Penny and escape.  We are lulled into thinking that in so doing they have prevented history from changing, or at least restored the original history; they have done neither.  As we saw previously, Sherman's trip to the present to collect Mr. Peabody created a two and a half millennium history in which Penny was queen to Pharaoh Tutenkamen.  This trip changes that, erasing that history and writing a new one, not the original history but one in which Tutenkamen was planning to marry the blonde only to have her kidnapped by enemies.  How that will change events is unclear, although it has a good probability of moving them back toward their original path.

A new history is now being written which must reach the twenty-first century before our travelers can arrive there, but it happens that they do not make it that far.  As whatever it is that powers the WABAC machine begins to fail, Peabody makes an emergency landing to visit Leonardo da Vinci, apparently a close friend he has visited before.  He works with da Vinci to create a machine that will provide enough power to propel the WABAC into the future, while the annoying Penny pressures Sherman to launch da Vinci's flying machine.  The flight is a success, although it is also a bit of a catastrophe, with Mr. Peabody concerned that Sherman might have been killed.

There are two significant points in this.

The second is that Sherman and Penny fly the glider.  Absent that, this would have remained an interesting speculation in da Vinci's notebooks.  Someone has said that it would have flown had he had a motor to power it, but a successful glider flight would have become known elsewhere, and the development of flight probably would have been accelerated.  Fortunately, the sticking point is still the motor--a device that required improvements to the piston, the development of the atomizer, the invention of the sparker, and the combining of these and several other unrelated technologies into a single idea--and thus it seems likely that no one would have launched an airplane prior to the early twentieth century.  However, there would have been more information about how to do it, and it might not have been the Wright Brothers who succeeded.  (That has other implications, including the photo of the time travelers in front of the Wright Brothers' bicycle shop, and a wealth of probable butterfly effects.)  However, it might have changed only the information that da Vinci's glider actually flew without altering anything else, so this is at least potentially not a problem.

However, there is the problem that Mona Lisa smiles.

The wonder of the enigmatic smile on the Mona Lisa is one of the prime points that makes the painting famous.  When Peabody arrives, da Vinci cannot persuade the girl to smile, so he cannot finish the portrait.  Peabody causes her to laugh, da Vinci captures the moment, and the painting is complete.  The problem is, even though at this particular moment Peabody has just come from the past, he originated in the future; that means that that particular smile could not have been seen on the face of the model in any previous history, and no one would have spoken of the smile on that painting.  Yet the painting is famous for the smile, and despite his many other accomplishments da Vinci is most famous for that painting and one other.

Let us suppose, then, that eventually the girl did smile, and da Vinci finished the painting.  We still have two problems.  The easy one is that with Peabody's intervention he finished the painting sooner and so had time in which to do something else; that is resolved because Peabody uses that time to build the energy generator.  The harder one, though, is that this Mona Lisa smiled because Peabody did something funny and she laughed.  That is probably not the enigmatic smile for which the painting is famed; da Vinci probably did not originally capture a smile from a laugh.  Thus it would seem that Peabody has spoiled the painting--the smile is wrong.

Of course, no one knows this because not even da Vinci knows the original smile.  As long as the painting is still famous and people comment on the smile, we probably have not severely altered history in a way which prevents it from confirming itself into an N-jump.  However, we now hit a problem that is more difficult to resolve, as the threesome leave Italy and are again diverted from their effort to return home.

Escaping the black hole, the WABAC machine crashes on the edge of the Trojan War giving us a new anomaly but a few complications.

Yes, the black hole is a bit unexpected.  We envision the WABAC moving through time and space, but if it is going from one point to another on Earth (and it has never, as far as memory serves, visited anywhere other than Earth) we do not expect it to travel far from the solar system spatially between stops.  The notion that their course might take them near a black hole is a bit ridiculous; but the writers needed something to explain why they crashed near Troy, and for a children's film "black hole" is probably better than "temporal vortex" or any other imagined temporo-spatial hazard, so we just go with it.

Scholars argue about the date of the Trojan War, and proposed dates range over several centuries from before the date of our Tutenkamen stop to considerably later.  That would be a problem, but that the film settles it for us as 1184 B.C., one and a half centuries after the 1332 stop in Egypt.  That means this anomaly is entirely contained within the previous one--probably.

To clarify, our travelers all left from the present--assume 2014--and traveled to Egypt, 1332 B.C.  They then came forward as far as the latter half of the fifteenth century to see da Vinci, and history from Tut to the Italian Renaissance was rewritten.  Departing from Italy they next landed near Troy, creating an anomaly whose future end is before the previous anomaly is resolved but whose past end is after the past end of the previous anomaly.  Given that, the second is contained within the first.  We have an AB1 timeline (original history of the first anomaly from the moment at which the time traveler will arrive to the moment of his depature) which is replaced by a CD1 timeline (the history created by the changes made by the time traveler), but in the CD1 timeline we have an AB2 and CD2 timeline (the histories created by the trip from Italy to Troy), all of it part of the CD1 history.  That is the situation as given.

The problems are that we do not quite understand how the WABAC works or what the black hole did.  It is a mistake to think that because black holes are a staple of science fiction they only exist in the future and the travelers must have overshot the mark, but it is equally a mistake to think that the black hole did not drag them beyond their temporal destination.  We simply do not know--and if indeed they traveled past the evening of the dinner party then history will have to advance to keep up with them, and there will be a version of events in which the Petersons are explaining to the police that the famed dog and his adopted son somehow kidnapped their daughter and escaped from the apartment unseen.  On the other hand, if the WABAC functions entirely "outside" time and space, then at the moment it encounters the black hole it is nowhere and nowhen, and it has no impact on events within time until it returns to timespace in Troy.

Our best guess suggests that the machine travels through time sequentially, much like driving a car, perhaps at velocities defined such as "ten years per minute".  Peabody seems to be steering it through space-like conduits, and when they run out of energy there is a sense that they have not traveled far enough, and thus that their temporal distance is connected somehow to their experiential time.  That, though, does not entirely answer the question.  We do not know whether they "drove" into the future beyond da Vinci before encountering the black hole, or whether they are traveling in some sort of parallel time that has no impact on real time until they cross back into the material world.  We thus can only guess, and it is most convenient for us if we guess that once out of timespace and traveling the machine is nowhen and nowhere and has no connection to real time.  That means that this incorporated anomaly can be defined as extending from da Vinci to Agamemnon.  The black hole causes them to crash in the past, but does not extend the future end of the anomaly.

Although the trip made from 2014 to Egypt has not been fully resolved, following the stop in Italy the trio travels back to Troy and becomes involved in the Trojan War.  They probably had no significant impact on the events of the war, but it is a very dangerous situation temporally--the fact that Sherman is involved on the battlefield might mean changes in who lives and who dies even if he kills no one, which raises our genetic problem, the problem of who will be born in the future.  One might think that events in 1184 B.C. are so far removed as to have little consequence in the present, but as it was with Tut the reverse is the case:  because family trees become ever more interlaced over time, the impact of a single death or survival could easily change the entire population of the world.  Yet since that did not happen, we can assume that there was no such change.

Our problem arises because Mr. Peabody gets left in the past, presumed dead.  Sherman and Penny do not know what to do about this--but it occurs to Sherman that the solution might be to travel to the future to a moment before Mr. Peabody leaves for the past and ask him what to do.  This is disastrous, although perhaps not for the reasons we see in the film.  Sherman has been warned that he should not travel to a time when he existed, but in this case he decides it is worth the risk.

Meanwhile, Mr. Peabody builds another WABAC (out of improbable components) and catches up a few minutes later.

Because Sherman and Penny arrive in the future first, we feel as if that is as it ought to be:  Mr. Peabody needs a bit of time to build his machine, and so Sherman and Penny leave from the past and arrive in the future, and then after (in some sense) they have arrived in the future Mr. Peabody leaves from the past and catches up with them in the future.  This, though, is not thinking clearly temporally.  From the time traveler's perspective a move forward in time is a bit like fast-forwarding history, and that's where we hit our confusion.

Let us suppose that it takes Mr. Peabody five years to build a new time machine.  That means Sherman departs from 1184 B.C. and Peabody departs from 1179 B.C.  Yet because Sherman is moving forward in history, he could in theory have as easily jumped from 1184 to 1179 to the moment when Peabody's machine is ready to go--and in fact there is a sense in which he did that, moving to 1179 and beyond as he heads for 2014.  Those five years which zoom past for Sherman take five years for Peabody--but all the same, when Sherman reaches 1179, Peabody is leaving for the future.  They thus in some sense leave 1179 at the same time.  The only logical reason for Mr. Peabody to arrive after Sherman is that he set the controls of his makeshift time machine to do so.

The question is why he would have done that, and the answer is not exactly obvious but comes with a bit of thought.

Arriving in the present, Sherman encounters himself.  He should have anticipated this, but then, he's a child.  The problem is that Peabody also encounters himself, and he certainly knows better than to travel to a time when he already exists--he undoubtedly wrote the rule and built the safety into the machine.  Why then is he there then?

First, we have something of a temporal continuity error.  Twice we see the scene in which Mr. Peabody is making his "Einstein on the Beach" cocktail.  The first time he is interrupted by Sherman coming for help retrieving Penny; the second time he is interrupted by Sherman and Penny coming for help figuring out what to do about the fact that Peabody died--or will die--in the past.  However, both interruptions occur at the same moment, that is, just as the umbrellas land in the drinks.  The problem is, when Sherman and Penny poke their heads into the room to ask to speak to him for a minute, where is the younger Sherman?  This Sherman says he is in Egypt with Penny, but that's clearly not true--in the previous history Sherman had already returned to get Peabody and not yet left with Peabody, but was standing right here talking.  Further, nothing Sherman and Penny have done would change that time.  They could have arrived a few minutes earlier--before Sherman returned without Penny--but since nothing they did will have changed the timing of those drinks, that did not happen.  Sherman should already have encountered himself.

The notion of the danger of a time traveler touching himself is a staple in time travel stories--for example, a disaster in Timecop.  We have explained why that is nonsense, but the real problem with encountering yourself is seen quite clearly here.

Older Sherman is here with older Penny as younger Sherman arrives.  Younger Sherman has just come from losing younger Penny in Egypt, so she is not with him.  Just as older Sherman came to enlist younger Peabody in the effort to save older Peabody, so, too, younger Sherman is arriving to enlist younger Peabody to save younger Penny.  Already the schedule is off--younger Peabody and Sherman do not leave on time to save younger Penny, so older Sherman and Penny cannot have arrived here and older Peabody cannot be following from the past.

Put more simply, what older Sherman and Penny do has changed their own histories such that Sherman will never take Peabody to Egypt to rescue Penny, and ultimately Sherman and Penny will not appear here to talk to Peabody.  That means that since they will never arrive here, they will not interfere with events at this moment, and so younger Sherman and Peabody will rescue Penny from Egypt and go through the events we have seen up to the moment when older Sherman and Penny arrive here to ask for help rescuing Peabody.  We have an infinity loop.

As to Peabody's arrival, it makes sense this far:  Peabody knows that (younger) Sherman came and took him away, and the time that has elapsed since that event is sufficient that his own younger self should have left for Egypt.  He did not anticipate that Sherman would have intervened and altered history such that the younger Peabody is still present, and so it was an unpredictable problem.  However, the fact is that older Sherman and Penny have already prevented the departure of younger Sherman and Peabody, and so history is trapped and cannot reach the moment of older Peabody's arrival.  That moment does not exist.  This is the kind of disaster that can happen when you encounter your temporal duplicate:  you change your own history such that you are not who you then were and thus are not who you are.  It is one of the most dangerous and complicated anomalies.

We still have the problem, though, that there are now two Peabodys and two Shermans present, and we add an angry and prejudiced Miss Grunion to the mix to get an explosive and disastrous situation.

We covered some of the complications created when Sherman duplicates himself last time, but the movie does something unanticipated.  As Miss Grunion grabs the two Shermans, they slap hands with each other and stick together.  Something then seems to draw them into each other, and as the temporally duplicated Mr. Peabodys attempt to prevent this they, too, are drawn into each other such that there is only one Sherman and one Peabody.

This is not less ridiculous than the similar (but very different) result in Timecop, in which the doppelgangers fused into a protplasmic mass and vanished from the world.  In that discussion we observed that the notion of the same matter occupying the same space when a person touches himself was complete nonsense on every level.  We know of no reason why touching your past or future self would be different from touching anyone else in the past or future, other than the difference created by meeting yourself and so changing your own history.

Besides, if this could happen it would lead to a far worse disaster.  Let us suppose that somehow this encounter has not led to an infinity loop--perhaps younger Sherman and Peabody still have time to make their trip to the past to rescue Penny.  The fact that the duplicates have now fused into a single version of each means history might never be resolved--far from preventing a paradox, this phenomenon has nearly guaranteed one.  It is absolutely essential to history that Peabody and Sherman--now the only ones who exist--leave immediately to rescue Penny in the past; yet that means that when they return to the present they will again encounter themselves.  This time the older Sherman might realize that he cannot touch the younger Sherman, and so they might avoid fusing; in that case, the younger Peabody and Sherman must immediately leave to rescue Penny.  However, when that younger Sherman returns as the older Sherman, he does not know not to touch his younger self, and so the fusing will happen.  We again have an infinity loop.  That is the temporal disaster we needed to avoid, and now it seems unavoidable.

The film, however, ignores this problem and suggests that the fusing of our heroes creates a different disaster, a sort of temporal rift through which objects in the past are being pulled to the present.  That gives us more problems.

One disaster begets another, and as the universe attempts to undo the paradox of duplicate persons by fusing the doppelgangers, it somehow opens a vortex through which objects are coming from the past to the present.  At this point it makes little sense already, since we have concluded that the fusing creates an infinity loop and thus that there is no moment in time after it.  However, we should take the rift as separate from the previous problems and see what something like this would do.

The rift brings us, in the order in which we see them, Leonardo da Vinci, Robespiere, Pharaoh Tutenkamen, the Trojan Horse with Agamemnon, Albert Einstein, Marie Antoinette, someone who is probably Ludwig von Beethoven, French soldiers, Greek soldiers, George Washington, Abraham Lincoln, Bill Clinton, the Sphinx, Isaac Newton, and more ancient debris.  There are other persons and objects around but none clearly identifiable.

The first problem is that each person or object brought to the future has vanished from some moment in the past.  Robespiere and Lincoln are both good examples, as their fame includes that the former was executed and the latter assassinated, but for most of the people involved at some point they died and that was recorded in history.  That never happened now; there is no mumified King Tut to be discovered in a treasure-filled tomb.  These people all vanished.

It is also noteworthy that most of those we see are people or objects who had some previous contact with the time travelers, and those few for which we are unaware of any such contact seem to recognize Peabody and so likely met him before as well.  This suggests that the rift is pulling people from moments visited by the time machine previously.  Peabody took Sherman to visit those people because they were, or would be, famous.  However, in pulling them out of history it is possible that the rift has caused them to cease ever to have been famous.  It is doubtful that Sherman would ever have visited Tutenkamen were it not for the discovery of Tut's tomb, and that tomb would not have existed if Tut had not remained in the past to die, so once Tut is pulled to the future it erases the visit Sherman made to Egypt, and in doing so might eliminate whatever it is which caused the rift to target Tut.  We again have a loop problem, since if Tut is pulled to the future he is not famous in the future, and if he is not famous in the future he is not pulled to the future.  This assumption might be wrong--the chosen individuals might not have been targeted because of a connection to Peabody in the future--but it is passing peculiar that the rift does not seem to have brought thousands of other famous persons not previously visited and has brought someone from every time visited during the trips in the movie.

Of course, before the movie ends all of these people will have been returned to their own times--which gives us another set of problems to be covered below--but at this moment, for the few minutes that they are in the future, there are millennia of history for which they were known to have vanished.  Further, the sheer number of them, all famous, is going to have given rise to theories concerning what became of them--abducted by aliens, snatched by God, hidden away by the Masons, sucked into Hell, gone into hiding so as to disguise their unaging immortality and so to emerge as someone else in the next generation.  By our time--remember, it seems to us that they were only absent for minutes, but they were actually absent for all the centuries that passed since their disappearance--there will be doctoral theses and scientific research attempting to find explanations for these vanishings.  It diverts resources from other subjects, and so changes what is known and what is invented in ways we cannot predict.

It might not prevent Peabody from adopting Sherman and inventing his WABAC, or Penny from getting in a fight with Sherman.  It is a butterfly effect issue:  will there be inadvertent major changes such as suggested by the genetic problem, or will we reach the present relatively unscathed?

Of course, since the rift seems to be continuing to pull from the past, the longer it remains open the more likely it is that it will pull something that matters, and so destroy time with an infinity loop, so it is vital that it be closed as quickly as possible.  That is what Peabody, with the aid of the gathered geniuses of history, attempts to do.

The film needed a solution to how to eliminate the rift once the writers had created the problem that the WABAC could not travel into the past so there was no way to prevent it from happening.  Sherman's suggestion is that they travel forward into the future, because he has never been there so it must not be disrupted yet.  Peabody then combines that with some statements made by several other geniuses which have nothing to do with each other or the problem to propose making a very fast very short trip to an instant in the future and letting the gravity created by increased mass from their velocity snap them back to hit the vortex and collapse it.

If you are scratching your head and saying, "how is that again?", good.  It is gobbledygook, arrant nonsense couched in big words to make it sound impressive.  That's all right--it's a cartoon, remember?  Just because we have been lulled into expecting it to make sense of some sort does not mean it makes sense of any sort.  Here it fails miserably.

We have already faced the problem that this rift might cause an infinity loop (and that the problem which caused the rift almost certainly must have done so).  That would mean that there is no future, that the time machine cannot go forward--but it would also mean that time has come to a screeching halt already, and there is no one to attempt to fix the problem because the present came to an end a moment ago.  So we will accept for argument that there is a future, that the rift has not yet destroyed time.

We also know that the WABAC is capable of traveling to the future, because it does that every time it travels to the past and returns--the return is a trip to the future.  It is wrong to think that it is simply a matter of returning to "the present", because when you are in ancient Egypt and you change something in the past and head for the future, that which you changed has become part of a history that must now be rewritten in its entirety in order for there to be a "present" somewhere in the future.  Such forward travel in essence involves speeding past all those changes, but the changes must all occur before you can land in the world that exists based on that history.  We want to think that when we are in the past the present exists, but when we are in the present the future does not yet exist, but that is not so:  when we are in the past, it is the present, and what we consider the present is the future, and it has no more nor less existence than the future has when we are in the present.  It must be created as we move into it, whether a minute at a time or at high time travel velocities.

That is the fundamental problem with Sherman's thought that the future has not been disrupted "yet".  If they depart from the "present" headed for the "future", the future will be written as they move into it.  If the rift exists now and nothing is done to resolve it now, traveling one minute into the future means that that minute of history will be written based on the fact that the rift exists now and is not about to cease to exist--and therefore the rift will exist at the future end of that minute.  You cannot escape to a future in which this has not happened (the problem with the ending of Millennium) because all futures are dependent upon the pasts that exist and support them.

So not only does the solution not work, it is not even really something that could be done.  Still, the film allows it to work, the rift reverses, and everyone and everything that was pulled to the future is returned to its place in the past--with some complications.

The film gives us what appears to be a happy ending.  All of our historic figures are restored to their proper places in history, although each has brought a bit of New York with him.  Sherman and Penny are best buddies.  Miss Grunion is no longer going to be a problem, as she, too, has found happiness as Mrs. Agamemnon.

That, though, could be a problem.

Maybe it is of little consequence that Washington and Franklin are showing off future money bearing their portraits; the bills won't last long, and no one will take them that seriously.  That Einstein struggles with a Rubik's Cube is a good gag, but not a history changer.  It might matter that Robespiere stuns himself with a TASER when facing arrest, but he was ultimately arrested and probably would not have escaped anyway.  So much about Agamemnon is lost or mixed with mythology at this point that it's not at all surprising that his pizza recipe would not have survived.  The souvenirs enjoyed by Tutenkamen and his court do concern me, as ancient Egyptian embalmers had surprisingly good ways of preserving all kinds of things in the royal tombs, and finding one of those foam fingers among the treasures would be something of a shock to archaeologists, but one way or another they probably would not have been saved.  There are only two problems that present a high probability of actually being problems.

The lesser concerns Leonardo da Vinci.  It seems that the experimental artist has brought several cans of spray paint back with him and is doing psychedelic airbrushed stencil images of his most famous portrait (while his most famous model learns to do impressive artistic spraypaint graffiti on a nearby wall).  If any of this material survives, it is going to raise significant questions about the painter.  Of course, experts will insist that these are forgeries, not at all like the style of the renaisance painter and using materials unavailable in the sixteenth century.  Besides, most of da Vinci's work has been lost to time because his experimentation often resulted in works with very short shelf life.  Perhaps his airbrush images will suffer the fate of most of his work, and be reduced to references in period books which modern scholars attempt unsuccessfully to interpret.  Time might survive.

The more serious problem is the 1184 B.C. marriage of Agamemnon to "the Grunion", a twenty-first century civil servant.  We have discussed the genetic problem before, and we have it again here:  would Agamemnon have married someone else?  Would someone else have missed a marriage in the hope of catching the general?  Will Mrs. Agamemnon have children, mixing her future genes into the past?  Does she in fact become her own great-great-great-so-much-greater-than-that-grandmother?  Does that change who she is in the future?

So the ending has the potential to destroy the film--but it is only potential.  It is remotely possible that no one was ever interested in marrying Agamemnon, that he has no children and would not have had any, that whatever impact all this from the rift has on the past is insignificant.

Of course, it is not really insignificant.  We talk as if returning everyone to history prevents the changes that would have happened, but it actually undoes the changes that did happen--all of history was changed by the disappearance of so many famous (and some not famous) persons, and now it is changed, not back but again, to a history in which they vanished briefly and then reappeared with tales of having visited the future, and sometimes with souvenirs to prove it.  Miss Grunion is only the most dangerous of such souvenirs.  We must hope that the new history is sufficiently like the old one that everything can stabilize.

It is a faint hope, but it could happen.

In all, the movie had its good moments, its good jokes, its entertaining parts, and its serious points.  It was worth watching, but it will be a long time before I, at least, have the motivation to watch it again.